CVE-2026-23743 (GCVE-0-2026-23743)

Vulnerability from cvelistv5 – Published: 2026-01-28 20:07 – Updated: 2026-01-28 21:07
VLAI?
Title
Discourse allows permalinks to restricted resources to leak resource slugs to unauthorized users
Summary
Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, permalinks pointing to access-restricted resources (private topics, categories, posts, or hidden tags) were redirecting users to URLs containing the resource slug, even when the user didn't have access to view the resource. This leaked potentially sensitive information (e.g., private topic titles) via the redirect Location header and the 404 page's search box. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. No known workarounds are available.
Severity ?
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
Assigner
References
Impacted products
Vendor Product Version
discourse discourse Affected: < 3.5.4
Affected: >= 2025.11.0-latest, < 2025.11.2
Affected: >= 2025.12.0-latest, < 2025.12.1
Affected: >= 2026.1.0-latest, < 2026.1.0
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Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.